Pen



FIG. 1 is a perspective view of a pen;

FIG. 2 is a left side elevational view, the right side being a mirror image thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a perspective view in an exploded condition; and,

FIG. 8 is a left side elevational view of FIG. 7, the right side being a mirror image thereof. 

The ornamental design for a pen, as shown and described. 